Stair structure



A. A. SWANSDN.

- STAIR STRUCTURE. APPLICATION man MAR.;:|. 1921.

Patented J U11-e 20, 1922.

ADOLF A. SWANSON, OFEVERETT, MASSACHUSETTS. 5

STA-IIR, STRUCTURE.

raaaa'aa Appiieation sled March 11, i921.` serial 110.451,492.

To all whom t may concern:

Be it known that L-Anonr A. SwANsoN, subject of the King of" Sweden,residing at Everett, in the county of Middlesex and State ofMassachusetts,` have invented new and useful Improvements in StairStructures, of which the following is a specification.

This invention relates to improvements in stair structures and has ,forits object to provide a cheap, simple, reproof stair structure of metaland concrete which will be very strong and may be easily and quickly yerected. v

Another object ofthe invention is to increase the strength ofthestringers by reinforcing the same with 'concrete 'which yis united witha body of concreteextending across the tread portion of the stairs.

Another object of the invention is-t0` pro-v vide a construction whichwill eliminate vthe vibrations usually occurring when stairs areconstructed of metal. l Still another object of the invention is toprovidel a novel means for locking Vthe step units in position whilebeing assembled kto prevent displacementl thereof prior to theapplication of the concrete and during the interval when the concrete ishardening.

The invention consists in the combination and arrangement of parts setforth in the following specification and particularly pointed out in theclaims thereof.

Referring to the drawings: l Figure 1 represents, a vertical sectionthrough a portion of a stair structure, said section being taken on theline 1-1 of Fig. 2. l Fig. 2 is a vertical section taken on the line 2-2of Fig. 1.

Like numerals refer to like parts throughout the several views of thedrawings.

In the drawings, 5 and 6 represent stringers. 5 constituting a wallstringerand 6 a well stringer. The wall Stringer 5 is formed of twoparallelly disposed plate 7 and 8 having flanges 9 and 1() respectivelyextending along their under edges, the fiange 9 resting upon the flange10. The plates 7 and 8 are spaced a suitable distance apart to form achannel 11 therebetween and said plates l are held in correct spacedrelation by rivets 12 which secure the flanges 9 and 10 .to-

gether, and shouldered studs 13 which are` VSpecification ofvLetterslfatent. Patented' June 20,1922,j

" parallellyl disposed plates 14..,and Y15' having y flanges -Iandf-l?"respectively extending along their under edges, the flange 17 rest-` ingupon the flange 16. VThe plates 14 and 6o i 15 are spaced a Ysuitabledistance apartk to form a channel 18 therebetween and said. plates areheld incorrect spaced relation byy rivets 12 which secure the flanges16`and 17 v together and shouldered studs 13 which are 65 riveted to theplates 14 and 15.' The flangesl 1.6 and r17 close the underside of thechannel 18'. i

.Y The plates 8 and 15 are each formed with horizontally vdisposed edges19 and verti- 70 cally disposed edges 20. Extending between thestringers and' and supported by the V plates 8 an'd'15 of saidstringersare` aY plurality of stepA units 21 `each comprising ahorizontally disposed tread support 22'which 75 restsy upon thehorizontal edges 19 of said plates and a vertically-disposed riserportion23 which rests against thegvertical edges 2O of said plates.Opposite end portions of the tread support 22 r are bentdownwardly 80vat 24 and extend into the channels-11 and 18 in the rear ofthe studs 13land a front edge 25 of said portions'24 contacts with the studs 13 whichprevent the step units 21` from moving forwardly upon the'horizo'ntaledges 85 19 of the plates 8 andr 15. y The upper 'portion of the riser23 is channel-shaped at 26 thereby forming aseat 27-"up'on'which thevfront portion of the treadv supportv 22 rests and also forming a flange28 which consti- 90 tutes the upper front corner of the finished units21 in positionduring'the erection of the structure priorto theyapplication ofthe concrete and during the hardening thereof, said meanscomprising clips 30 which'are 100 mounted upon the studs 13. lThe clips30 are preferably constructed of spring'steel and are approximatelyU-shaped in form, having vertically disposed members 31 and 32 throughwhich the studs 13 project, ysaid 1,05 members being located adjacent totheinner surfaces of theplates forming the stringers 5 and 6. The member32 is provided with aV bent portion 33 at its upper extremity which isadapted to spring' over the tread 110 support 22 as illustrated 1nFigure 2v and thereby prevent ,said tread' support from also provides'apractical and durable antislip tread surtac'e'lor the steps. Moreoverthe 'tart thatv the concrete comprising the tread portiouunitesW-itlrthe concrete Within the channels otL the stringers makes a moresolid structure and prevents the vibrations which usually occur instairs constructed el metal.

While l have illustrated and? described a preferred construction ot stepunits and Stringer-s, it Will be evident to those skilled inthe artlthat many modifications thereofE may be arranged-Without. departingfromfthe spirit-rot. theinventiomall ot' Whichmay be Within the scopefctthe. appended claims.

1. In a stair structurea pair ol stringere each providedwith a channelformed therein, a plurality of step unitsv mounted upon said' stringerseachcomprising a-tread' support and a riser portion and' a continuousbody of reproot material located Within said channels and extendingacross said Vtread support. y K

2. Ina stair structure'al pair ot strangers each provided With achannely formedtherein, a body ol concrete located Within said channels,a` plurality7 ot stepvunits mounted upon saidstringers,each comprisingatread support and a riser portiony andy a body of' concrete located uponsaid tread support and intersecting'the-concrete oitY said channels.

3. In a stair structure a pair of' stringers eaclr comprising a pair ofparallel plates formingy a? channel therebetween, said channels beingclosed upon the underside thereoli,`

a pluralityl ott step units mounted upon said stringere, eachcomprisingfay tread support and a riser portion and a continuous body offireproof materiali located Within said channelsand extending acrosssaidv tread support. c c

a. In aY stair structure a pair of stringers each" comprising` a. pairot parallel plates forming al channel therebetween', said channels beingclosed upon the underside thcreof, a plurality ot step units mountedupony said stringers,v eachK comprising a tread support anda riserportion and ai continuous' body of concrete located Within. saidchannels and!v extending .acrossv said tread supports.v

5. lnl a stair structurel a. pair of. stringere each comprising a pairof parallel plates' forming a channel therebetween, said cha-nnels beingclosedI upon the underside thereoi, a plurality of studs located betweenand separating said plates, a plurality et step units mounted upon saidstringers, each comprising a tread support anda riser por'- tion, meansmounted upon said studs and engaging said step unitsV to prevent saidunits `from liftingv upon said string-ers and a-bedy ol* concretelocatedWit-hin said channels and extending across-said treadsupports.

6. ln a: stair structure a pair of' stringere` eachv comprising a= pairot parallely platesforming a channel therebetween, said chan nels beingclosed upon the underside there-ot, av plurality of step units mountedupon said stringere, each comprising a tread supporti anda riserportion, said tread support having: flanges atthe oppcsiteends thereofex tending intofsaid channels,` a plurality of studs separating saidplates and preventingl a forward movement of saidy step units upon saidstringers, spring clips mounted upon; said studs and engaging saidstepunits to prevent saidv units from lifting upon said stringers and abody ot concrete located within said channels and extending across saidtread 'supports'.

7. ln a stair structure arpa-ir ot stringers each comprising a pair ofparallel plates` forming a channel@ therebetween, said channels beingfclosed uponthe underside thereof, one of: the-plates'ot each Stringerbeing provided With a pluralityv of: horizontallyT disposedcdges, aplurality of step-units mount ed upon saidI horizontal edges, eachcomprising al tread support and a riser portion, said tread supporthaving flanges at the opposite ends thereof extending into said'chan'-nels, a plurality et studsv separating the plates ot each Stringer andpreventing tor- Wardmovemcnt of said step'units uponsaid horizontaledges, spring clipsv mounted upon said studs and engaging said stepunits to prevent said units from, lifting upon said horizontal edges anda body ofi concrete l0- catcd within saldi channels and extending acrosssaid tread supports.v Y

8.- ln a stair structure a pair oit stringers each comprising a pair ot'parallel platesforming a channel therebetween, said channels beingclosed upon the underside thereof, one ofv the plates of each Stringerbeing provided 'WithaL pluralityof horizontally disposed edges, aplurality ot step units mounted uponfsaid horizontal edges, each comprising a tread support and a.' riser portion, said tread support havinganges at the-opposite ends thereof extending int-o said: channels, aiplurality ot studsl separating the plates of eachstringer and.preventing' a forward. movement of said stepunitsV upon saidh'orizontalf edges, lli-shaped spring clipsmountfed lSO Vio

upon said studs and embodying therein a pair of resilient members, oneof said members having a projection formed thereon engaging said treadsupport to prevent said units from lifting upon said horizontal edgesand a body of concrete located within said channels and extending acrosssaid tread supports. i

9. In a stair structure a pair of stringers each comprising a pair ofparallel plates forming a channel therebetween, said channels beingclosed upon the underside thereof, one of the plates of each stringerbeing provided with a plurality of horizontally disposed edges, aplurality of step units mounted upon said horizontal edges, eachcomprising a tread support and a riser portion, said tread supporthaving flanges at the opposite ends thereof extending into saidchannels, a plurality of studs separating the plates of each Stringerand preventing a forward movement o said step units upon said horizontaledges, U-shaped spring clips mounted upon said studs and embodyingtherein a pair of resilient members, one of saidvmenibers having aprojection formed thereon engaging said tread support to prevent saidunits from lifting upon said horizontal edges and a body of concretelocated within said channels and extending across said tread supports,-said concrete preventing ksaid spring clips from being disengaged fromsaid step units.

In testimony whereof I have hereunto set my hand in presence of twosubscribing wit- 35 nesses.

ADOLF A. SWANSON. Witnesses:

FRANKLIN E. LOW,l

HERMAN R. HOFFMAN.

